The present invention relates to an analogue alarm electronic timepiece which is simple in construction and which uses the time-indicating hands to set the alarm time.
FIG. 1 illustrates one example of a block diagram of the conventional analogue alarm electronic timepiece. An oscillating circuit 1 produces a high frequency signal as a time standard signal. A frequency dividing circuit 2 divides down the high frequency signal and produces a signal for operating the following circuits. A driving circuit 3 synthesizes an output signal from the frequency dividing circuit 2 and periodically generates driving pulses having suitable proper pulse width for driving a motor. A motor 4 converts the driving pulses into a rotary mechanical motion. A display mechanism 5 has a gear train and time hands, and the display mechanism 5 transmits the motion of the motor 4 to the time hands and displays the time. An alarm time setting mechanism 7 is provided for setting and displaying an alarm time, and the setting and displaying operation is carried out by moving an alarm setting wheel or a sub-hand which is operated by the operator. A coincidence detecting mechanism 6 is a switch mechanism operated in relation to the display mechanism 5 and the alarm time setting mechanism 7 such that when the present time is coincident with a preset alarm time, the coincidence is detected in accordance with the ON-OFF condition of the switch mechanism and an electric signal is produced. An alarm circuit 8 synthesizes an alarm driving signal on the basis of the output signal from the frequency dividing circuit 2, and the circuit 8 outputs the alarm driving signal when the coincidence detecting mechanism 6 detects the fact that the present time is coincident with the alarm time. An electric-acoustic transducer 9 comprises a piezo-electric element or an electromagnetic speaker for converting the alarm driving signal into a sound signal by generating an audible sound.
The above mentioned analogue alarm electronic timepiece is disadvantageous in that since the mechanical constructions of the alarm time setting mechanism 7 and the coincidence detecting mechanism 6 are complex, it is difficult to obtain a small size timepiece or a thin type timepiece, and the cost is high. Moreover, since a special display device is required for setting and displaying the alarm time, this restricts the freedom of design for the outer design for a timepiece. Furthermore, in such an alarm electronic timepiece, since the coincidence detecting mechanism 7 is a mechanical switch, it is difficult to exactly set an alarm time in the time unit of minutes or seconds.